Background

Rates of many surgical procedures vary widely across both large and small geographic regions.

Although variation in health care use has long been described, few studies have systematically compared variation profiles across surgical procedures.

The goal of this study was to examine current patterns of regional variation in the rates of common surgical procedures.

Methods

The study population consisted of patients enrolled in Medicare in 1995, excluding those enrolled in risk-bearing health maintenance organizations.

Patients ranged in age from 65 to 99 years.

Using data from hospital discharge abstracts, we calculated rates of 1 common inpatient procedures for each of 306 US hospital referral regions (HRRs).

To assess the relative variability of each procedure, we determined the number of low and high outlier regions (HRRs with rates<50% or>150% the national average) and the ratio of highest to lowest HRR rates.